Introduction to Geology --Discussion http://serc.carleton.edu/NAGTWorkshops/online/courses/46408.html#discussion One analogy to ... http://serc.carleton.edu/NAGTWorkshops/online/courses/46408.html#post21485 Kenneth Sutton 1343076600 http://serc.carleton.edu/NAGTWorkshops/online/courses/46408.html#post21485